1. Field of the Invention
The present invention relates to a method and system for providing a multicast service in a next-generation network (NGN), which can improve the quality-of-service (QoS) of broadcast services by separating a routing path calculation function and a resource allocation function during the setting of a multicast broadcast channel and performing centralized resource control.
The present invention was partly supported by the IT R&D program of Ministry of Information and Communication (MIC) and Institute for Information Technology Advancement (IITA) [Project No.: 2006-S-058-02, Project Title: Development of Network/Service Control Technology in All IP-based Convergence Network]
2. Description of the Related Art
A next-generation network (NGN) is a voice/data converged network, which is created by incorporating nearly all types of communication networks such as a typical telephone network and a wireless communication network into a packet-based common network and can thus reduce the cost of the establishment and management of a network and provide various flexible and versatile network solutions and applications.
In order to receive a multimedia broadcast program from an NGN, a terminal such as a set-top box may be provided with electronic program guide (EPG) information by a broadcast control server, and a user may choose one of a plurality of broadcast channels with reference to the EPG information. Once the user chooses a broadcast channel, the terminal may issue a request for joining a multicast group by using a multicast group identifier (ID) allocated to the chosen broadcast channel. According to a typical multicast protocol, a routing protocol in a multicast router begins to be executed upon receiving a request for joining a multicast group from a user. Thus, a routing path is calculated, and at the same time, a path is set. Then, multicast traffic is transmitted.
However, a multicast router may not be able to determine the resource state of a whole network and may thus have to calculate a routing path based on the resource state of each individual router. In addition, since there is no network equipment responsible for the allocation of resources, it is almost impossible to guarantee an effective allocation of network resources.